Other Useful Links

ArduinoPlusPlus Blog:

• About the YX5300https://arduinoplusplus.wordpress.com/2018/07/23/yx5300-serial-mp3-player-catalex-module/
• Message Flow https://arduinoplusplus.wordpress.com/2019/04/25/yx5300-serial-mp3-player-message-sequencing/
• Making an MP3 Player https://arduinoplusplus.wordpress.com/2019/xx/xx/yx5300-mp3-player/

The Catalex documentation for their modules:

• Catalex_YX5300_Docs.zip files (Chinese) http://pan.baidu.com/s/1hqilpB2

This library also integrates data and ideas from a number of other places:

• (French) https://andrologiciels.wordpress.com/arduino/son-et-arduino/mp3/catalex-mp3-serie/
• (Polish) http://www.jarzebski.pl/arduino/komponenty/modul-mp3-z-ukladem-yx5300.html
• (French) https://www.carnetdumaker.net/articles/utiliser-un-lecteur-serie-de-fichiers-mp3-avec-une-carte-arduino-genuino/